package middleware

import (
	"ip_server/util"
	"fmt"
	"github.com/gin-gonic/gin"
	"ip_server/logger"
	"net/http"
	"strings"
	"time"
)

// 预处理中间件
func RequestMiddleHandler(c *gin.Context) {
	c.Set("start_time", time.Now())
	method := c.Request.Method               //请求方法
	origin := c.Request.Header.Get("Origin") //请求头部
	var headerKeys []string                  // 声明请求头keys
	for k, _ := range c.Request.Header {
		headerKeys = append(headerKeys, k)
	}
	headerStr := strings.Join(headerKeys, ", ")
	if headerStr != "" {
		headerStr = fmt.Sprintf("access-control-allow-origin, access-control-allow-headers, %s", headerStr)
	} else {
		headerStr = "access-control-allow-origin, access-control-allow-headers"
	}
	if origin != "" {
		c.Writer.Header().Set("Access-Control-Allow-Origin", "*")
		c.Header("Access-Control-Allow-Origin", "*")                                       // 这是允许访问所有域
		c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE,UPDATE") //服务器支持的所有跨域请求的方法,为了避免浏览次请求的多次'预检'请求
		//  header的类型
		c.Header("Access-Control-Allow-Headers", "Authorization, Content-Length, X-CSRF-Token, Token,session,X_Requested_With,Accept, Origin, Host, Connection, Accept-Encoding, Accept-Language,DNT, X-CustomHeader, Keep-Alive, User-Agent, X-Requested-With, If-Modified-Since, Cache-Control, Content-Type, Pragma")
		//              允许跨域设置                                                                                                      可以返回其他子段
		c.Header("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers,Cache-Control,Content-Language,Content-Type,Expires,Last-Modified,Pragma,FooBar") // 跨域关键设置 让浏览器可以解析
		c.Header("Access-Control-Max-Age", "172800")                                                                                                                                                           // 缓存请求信息 单位为秒
		c.Header("Access-Control-Allow-Credentials", "false")                                                                                                                                                  //  跨域请求是否需要带cookie信息 默认设置为true
		c.Set("content-type", "application/json")                                                                                                                                                              // 设置返回格式是json
	}
	//放行所有OPTIONS方法
	if method == "OPTIONS" {
		c.JSON(http.StatusOK, "Options Request!")
	}
	//生成logId
	logid := util.GenerateLogid()
	err := c.Request.ParseForm()
	if err != nil {
		panic(err.Error())
	}

	logger.Debug(logid, "**************** Client : ",
		c.Request.RemoteAddr, " [", c.Request.Method, "] ", c.Request.URL.Path, " ****************")
	logger.Debug(logid, "request : [", c.Request.URL, "] ", c.Request.PostForm)

	//设置logId
	c.Set("logid", logid)
	c.Next()
}
